Oral care device with a function element and method of manufacturing it

ABSTRACT

An oral care device having a handle and a head connected or connectible thereto, on which oral care elements are provided. An electrically operable function element is arranged on an outer surface of the head and an elastomer element is disposed adjacent the function element.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part application of prior copending International Application No. PCT/IB2009/053811, filed Sep. 1, 2009, designating the United States.

FIELD OF THE INVENTION

This invention relates to an oral care device and to a method of manufacturing it.

BACKGROUND OF THE INVENTION

Known from the prior art are various oral care devices such as toothbrushes having an electrically operable function element such as an LED emitting light. Efforts have been made in this context to arrange the LED within the toothbrush head so that the electrically operable function element is fully encapsulated in the toothbrush plastic and hence no moisture-related problems are encountered. Other efforts have been made to arrange the function element as near as possible to the teeth to be cleaned. However, such efforts can lead to handling problems during use.

It would thus be desirable to provide an oral care device that enables an arrangement of an electrically operable function element on the head near to the oral care site, for example, the teeth or the tongue, while providing for safe and user-friendly handling.

Further advantages and application possibilities of the present invention will become apparent from the subsequent description of embodiments with reference to the accompanying drawings. It will be appreciated that any feature described and/or represented by illustration, when used singularly or in any meaningful combination, forms the subject-matter of the present invention, irrespective of their summary in the claims or their back-reference.

SUMMARY OF THE INVENTION

An oral care device that has a handle and a head that has an outer surface. The head is connectible to the handle. The device comprises oral care elements disposed on the head and an electrically operable function element disposed on the outer surface of the head, and an elastomer element is disposed adjacent to the function element.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the head and the neck portion of an oral care device according to an embodiment of the invention;

FIG. 2 is an enlarged perspective view of the head of FIG. 1;

FIG. 3 is a top plan view of the head of the oral care device of FIG. 1;

FIG. 4 is a longitudinal sectional view taken along the line A-A of FIG. 3;

FIG. 5 is a cross-sectional view of the head taken along the line C-C of FIG. 3;

FIG. 6 is a perspective view of the elastomer element of the oral care device of FIG. 1;

FIG. 7 is a top plan view of the elastomer element of FIG. 6;

FIG. 8 is a side view of the elastomer element of FIG. 6;

FIG. 9 is a front view of the elastomer element of FIG. 6; and

FIG. 10 is a longitudinal sectional view of a head of an oral care device with electrically operable function element of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a perspective top plan view of the head of an oral care device, which according to this embodiment, is part of a manual toothbrush. FIG. 2 is a somewhat enlarged perspective view of the head of the oral care device of FIG. 1. In both FIGS. 1 and 2 as well as in the following Figures, the remaining components of the toothbrush are not shown but are provided as known from the art. A neck portion 2 adjoins the head 1 which has a bristle zone on an upper side for cleaning the teeth. At the breakaway line 3 of FIG. 1 the neck portion continues in a handle portion in which electric leads for operating an electric function element are installed. The handle portion also accommodates an ON/OFF switch, a power supply and other electric devices necessary to operate the electric function element. The oral care elements provided for this embodiment are tufts of cleaning bristles 5 which can be fastened in the head 1 in every manner known in the art. According to the present embodiment, the tufts of cleaning bristles are anchored in the head using the anchor tufting method. Other oral care instruments, for example, elastomer cleaning elements, which are fastened in or molded on the head, can be provided as an alternative or in addition.

The outer surface 6 of the head, on which the oral care elements can be fastened, may include in the front half of the head or in the front third of the distal end of the head 1 the function element 7 and the elastomer element 8 arranged around the function element. Both the function element 7 and the elastomer element 8 are constructed such that they protrude from the outer surface in the direction of the bristle ends. In an alternative embodiment, the elastomer element and the function element may be arranged on another surface which is devoid of tooth cleaning bristles 5. This could be, for example, the rear side or the side of the head 1. In the present case the outer surface 6 is a uniformly plane surface which includes apertures for receiving the oral care elements. According to the present embodiment, the outer surface 6 is also the tufting surface for the bristle tufts. Alternatively, the outer surface 6 can also have a topography differing from the plane surface, with “outer surface 6” being understood to mean the surface into which the oral care elements are inserted and secured in the head 1 adjacent to the elastomer element 8. According to the present embodiment, an LED is provided as function element 7.

As illustrated in FIGS. 1 and 2, the present embodiment includes two outer rows of bristle tufts which are inclined towards the handle, and two inner rows of bristle tufts which are inclined towards the distal end. One front group of bristle tufts is arranged at the distal end to better reach wisdom teeth, for example. The configuration of oral care elements (bristle tufts, for example) can be varied and combined with the elastomer element and the function element in any desired way. According to the present embodiment, the elastomer element 8 is arranged in the front distal end third of the head 1 and is surrounded by bristle tufts on all sides. The function element or LED 7 is fully or, alternatively, partly surrounded by the elastomer element 8.

FIG. 3 shows a top plan view of the head 1. As is clearly evident from this Figure, the LED 7 is not covered by bristle ends or bristle portions, which enables an unobstructed illumination of the teeth. Provided around the LED is a free region which has a diameter of 2 to about 4 mm and is devoid of bristles. This diameter range relates to the optical axis of the LED or an axis angled or offset relative to it. The LED is surrounded by cleaning bristles or oral care elements essentially on all sides.

FIG. 4 shows the head 1 in a longitudinal sectional view along the line A-A of FIG. 3 which corresponds to the longitudinal axis 9. In this embodiment, the LED protrudes beyond the plane outer surface 6 of the head 1 by about 1 to about 3 mm. Free ends 11 of the elastomer element 8 project from the outer surface 6 by about 5 to about 9 mm, or about 6 to about 8 mm. The longest bristles used on the head 1 project away from the outer surface vertically upwardly by about 10 to about 12 mm so that there is preferably a difference of between about 3 and about 5 mm between the longest cleaning bristles 12 and the free ends 11. This difference can be provided independently of the above length ranges. Thus, tooth cleaning is performed substantially by the cleaning bristles, whereby the free ends 11 of the elastomer element 8 may also perform cleaning functions, depending on the brushing technique used. The elastomer element 8 may have a hardness of 50 to 80 Shore A. Even on intensive pressing of the bristles against the teeth it is thus not likely to compress the elastomer in its longitudinal dimension to an extent causing the teeth to contact the LED 7.

FIG. 5 is a cross-sectional view along the line 10 or C-C of FIG. 3. As becomes apparent from both FIGS. 4 and 5, a foot region of the elastomer element 8 is arranged in direct adjacency to bristle tufts. The distance between the cleaning bristles nearest the elastomer element and the wall of the elastomer element at the level of the outer surface 6 amounts to between a few tenths of a mm and about 2 mm. The LED 7 may be press-fitted within a hard plastic opening of the head 1. According to this embodiment, the sections of the elastomer element 8 are only connected to the outer surface 6 and not to the mounting hole for the LED, whereby a firm and sealing press-fit is obtained between the hard plastic of the LED and the hard plastic of the head 1.

FIG. 6 is a perspective view of the elastomer element 8. FIG. 7 shows this elastomer element in a top plan view, FIG. 8 in a front view, and FIG. 9 in a side view. According to this embodiment, the elastomer element 8 includes four free ends 11, but in variations it may also have two, three or more than four ends 11. The four free ends 11 are connected to each other in the base area by a circumferential wall, with indentations 13, 14 and 15 being provided between the ends 11. The indentations or recesses or cutouts 13 extend downwardly deeper than the LED 7 protrudes from the outer surface 6 of the head 1. It is thereby ensured that liquid or toothpaste can be drained on two sides and the optical quality of the LED's radiation performance is not adversely affected. A minor impairment of the optical quality of the LED's radiation performance is considered uncritical. Generally, however, the aim is to design the elastomer element 8 and its surrounding geometries to the effect that no major amounts of liquid or toothpaste or none at all can accumulate within the elastomer element 8 and/or on the LED 7. The recesses 13 may be provided on both sides of the elastomer element 8 as V-shaped notches. The cutout 14 may be arranged in an about 90° offset position between the recesses 13 in the wall of the elastomer element, thereby enabling a better emission of light through this opening on the one hand and sufficient flexibility of the ends 11 of the elastomer element 8 on the other hand. Provided on the side close to the distal front end of the head is another cutout 15 which in this embodiment is equally U- or V-shaped and arranged on the outer wall in an about 90° offset orientation relative to and between the recesses 13.

A similar effect can be achieved using an alternative elastomer element 8 which comprises a plurality of individual rods of either round, oval or rectangular cross-section arranged around the LED, because gaps are likewise formed between these rods which lend these elements sufficient flexibility and allow the liquid to be drained. In this alternative embodiment, the plurality of elastomer elements 8 without a shared foot or base ring of the type shown in FIGS. 6 to 9 are preferably connected with each other through a base or molding area in the head 1. The cutouts and recesses 13, 14 and 15 also help ensure that directly adjacent bristle tufts do not contact the elastomer element or are deformed thereby.

As becomes apparent particularly from FIGS. 6, 7 and 8, the elastomer element has an additional indent 16 causing the ends 11 to extend in a frusto-conically tapering configuration, rather than cylindrically, relative to the base diameter of the elastomer element 8. The indent 16 serves equally to ensure generally unhindered movability of the adjacent bristle tufts (in this connection see in particular FIG. 4) on the one hand and manufacturability of the bristle ends adjoining the elastomer element.

The toothbrush may be manufactured using the following manufacturing steps. The head 1 may be produced applying the plastic injection-molding technique. Depending on whether the elastomer element 8 is injection-molded separately and then secured to the head or whether it is desired to manufacture it integrally with the head, the head 1 is produced optionally with the elastomer element 8 using the two-component injection-molding technique. The head may be equipped with bristles by anchor wire tufting method (stapling technique). Other known possibilities of securing the bristle tufts or other oral care elements can be used alternatively to fasten oral care elements to the head. The function element, which in this case is an LED, is also mounted in the head.

In the event that the LED is not to be mounted in the head but injection-molding around it, the manufacturing steps may include injection-molding of the head with molding around the function element, connecting the elastomer element with the head or injection-molding the elastomer element onto the head with a second plastic component, and tufting the head. The head tufting operation may include not only the fastening of the bristle tufts to the head but also the further treatment steps on the bristle ends. These further treatment steps may include trimming the bristles to length and endrounding the bristle ends. Alternatively or optionally, additional final treatment steps can be performed on the bristle ends. According to this embodiment, the topography of the bristle ends exhibits a structure differing significantly from a flat plane because individual bristle tufts are longer or shorter than adjacent bristle tufts. The bristle tufts of one length remain at their mounting sites for further treatment, that is, for trimming to length and endrounding, while bristle tufts of other lengths are temporarily bent to the side using, for example, so-called displacement bars. Subsequently, the endrounded bristle ends are bent to the side with the displacement bars and the still untreated bristle tufts are cut to their proper length and each single filament of the tuft is endrounded. In this context it will be noted that the elastomer element 8, owing to its indents and cutouts, may also help by providing a means for the displacement bars to be used without causing problems for final treatment of the bristle ends.

FIG. 10 shows the head 1 in a longitudinal sectional view. The elastomer element 8 may be secured to the head 1 prior to fastening the LED to the head and prior to fastening the bristle tufts to the head 1. FIG. 10 shows the installation of the electrically operable function element in the head 1 schematically. Provided as electrically operable function element is an LED 7 whose connection wires with a wire connection 17 are equipped separately with an encapsulation 18. This protects the electric connections of the LED 7 and the connection wires 17 from moisture ingress. The LED 7 may be inserted from the rear through the brush head and a larger cavity 19 so that there is also space for accommodating the encapsulation 18 in the cavity 19.

The electric wire 17 may be passed through a hollow space in the toothbrush neck which connects the head to the handle and the electric components contained therein. The LED 7 may be pressed into the hole 20 with a press fit. According to this embodiment, both the LED 7 and the head 1 are made from a hard plastic material so that a slightly smaller dimensioning of the hole 20 in the head compared to the outer diameter of the LED 7 is suitable for a press fit.

Alternatively, the LED 7 or the head 1 is formed at least partly from a soft plastic material such as TPE. The head material can be optionally transparent or translucent. The head may be sealingly closed from the rear with a cover 21 (see FIGS. 4 and 5) following insertion of the LED 7 and the encapsulation 18. The LED can be fastened in the head by any other method. An alternative production method involves, for example, injection-molding around the LED in the die in which the head 1 is injection-molded. As other alternatives, the LED can be welded in, fitted in, adhesive-bonded or cast in. Also, the LED (or the function element) can be installed from above (that is, from the bristle plane) or between halves of the head.

Similar variants are possible for the construction of the elastomer element 8. The elastomer element 8 may be injection-molded with the head 1 in one integral piece. Alternatively, the elastomer element is produced in a further injection-molding step, is adhesive-bonded, joined, welded or snap-fitted. The elastomer element can also be made of a different flexible material.

An elastomer element disposed directly adjacent to the function element can help ensure that the function element does not negatively affect the user when cleaning the tooth or the tongue. Furthermore, the embodiment of the invention enables the electrically operable function element to be arranged in close proximity to the teeth (or the tongue) to be cleaned while at the same time the thickness of the head carrying the oral care elements is kept suitably small. As such, the toothbrush continues to occupy a small space between the inside of the cheek and the outer surface of the tooth, so as to provide handling comfort.

The elastomer element may be constructed as a circumferential wall around the function element. This provides for a uniform supporting function covering the entire circumference of the function element by the wall of the elastomer element. The construction of the elastomer element as a circumferential wall affords greater ease of manufacture and enables absorption of force within the elastomer element by neighboring wall sections.

The circumferential wall may include lateral recesses arranged on a height with the function element. The provision of the recesses on a height with the function element ensures that toothpaste, instead of accumulating within the elastomer element on the function element, can be drained through the lateral recesses. A closed cup-type structure of the elastomer element is therefore considered as disadvantageous.

At least two elastomer elements may be arranged laterally adjacent to the function element. For example, the elastomer elements can be constructed as two shells or as two elastomer elements shaped, for example, as rectangles, which on either side are arranged in direct adjacency to the function element and as such also enable a sufficient supporting effect, wherein the interruption between the two elastomer elements produces a gap through which liquid or toothpaste which might deposit on the function element is drained straight away. Instead of two elastomer elements it is also possible to arrange three, four, five, six, seven or more elastomer elements around the function element. These elastomer elements are movable essentially independently of each other or are at least flexible in the end region and may share a base region adjacent to the head or in the head.

The function element and the elastomer element may be integrally made of one piece. Accordingly, the function element and the elastomer element are preferably formed of the same material. Alternatively, the function element and the elastomer element may be made of two materials.

The elastomer element may include at least two free ends opposite the outer surface. The free ends are formed, for example, by a wavy structure of the ends or topography of the elastomer element, by indentations or recesses or elastomer elements that are movable or bendable independently of each other. Depending on the dimensioning, the free ends can be adjusted to a certain resilience or be constructed for an optimum cleaning effect on the teeth or the tongue.

The function element may be arranged adjacent to and/or between the oral care elements. Thus, the properties of the function element take effect in the immediate vicinity of the oral care elements. Alternatively, the function element may be arranged on another outer side of the head which is devoid of oral care elements. This could be of particular interest for a tongue cleaner with function element, for example.

The function element may be constructed as a light emitting source, in particular as an LED (light emitting diode), as a sensor or an actuator for, for example, a sound, a movement or a vibration. The LED can be used, for example, as a supplier of energy for activating a substance in the toothpaste. Other energy-emitting function elements may be used alternatively. If the function element is constructed as a sensor, then this can be, for example, a motion sensor which detects the 3D motion of the head by means of an inclination sensor, a speed sensor or an acceleration sensor. Also a contact force sensor may be contemplated.

The function element may be arranged partly in the head and partly projecting therefrom. The elastomer element arranged directly adjacent to the function element thus prevents that, for example, a tooth to be cleaned can hit directly against a function element formed, for example, of a hard plastic material.

The elastomer element may be made of a thermoplastic elastomer and the head, in particular the areas adjoining the elastomer, of a hard plastic material as, for example, PP, POM, copolyester or PE.

The oral care device may be constructed as a manual or electric toothbrush and/or the function element as an LED which is arranged in protruding fashion in the cleaning region. The LED or the function element may be arranged centrally or in the front half, that is, the half of the head at the end remote from the handle. This helps ensure that also the posterior molars can be illuminated well.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.”

Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. 

1. An oral care device having a handle and a head having an outer surface, the head connectible to the handle, the device comprising oral care elements disposed on the head; an electrically operable function element disposed on the outer surface of the head; and an elastomer element is disposed adjacent to the function element.
 2. The oral care device according to claim 1, wherein the elastomer element is constructed as a circumferential wall around the function element.
 3. The oral care device according to claim 2, wherein the circumferential wall includes lateral recesses arranged on a height with the function element.
 4. The oral care device according to claim 1, wherein at least two elastomer elements are arranged directly laterally adjacent to the function element.
 5. The oral care device according to claim 1, wherein the function element and the elastomer element are integrally made of one piece.
 6. The oral care device according to claim 1, wherein the elastomer element includes at least two free ends opposite the outer surface of the head.
 7. The oral care device according to claim 1, wherein the function element is arranged adjacent to and/or between the oral care elements.
 8. The oral care device according to claim 1, wherein the function element is a light emitting source, a sensor or an actuator.
 9. The oral care device according to claim 1, wherein the function element is disposed partly in the head and partly projecting therefrom.
 10. The oral care device according to claim 1, wherein the elastomer element comprises a thermoplastic elastomer.
 11. The oral care device of claim 10 wherein the head comprises PP, PE, copolyester or POM.
 12. The oral care device according to claim 1, wherein the function element is secured in the head by a press fit.
 13. The oral care device according to claim 1, wherein the elastomer element protrudes from the outer surface of the head by at least about 4 mm and that other oral care elements are provided having their ends spaced from the outer surface by a larger distance than the elastomer element.
 14. The oral care device according to claim 1, wherein the oral care device is a manual or electric toothbrush and the function element comprises an LED which is disposed in a protruding arrangement in the cleaning region.
 15. A method of manufacturing an oral care device, comprising the following manufacturing steps; injection-molding a head; connecting an elastomer element to the head; tufting the head; fastening the function element adjacent to the elastomer element.
 16. The method according to claim 15, wherein the elastomer element is injection-molded onto the head using a multi-component injection-molding technique.
 17. The method according to claim 15, wherein at least two tufts of bristles are tufted to the head and wherein one group of bristle tufts is bent and a second group of bristle tufts is cut to length and/or endrounded.
 18. The method according to claim 15, wherein the function element is secured in the head by means of a press fit.
 19. The method according to claim 15, wherein the head includes hard pleastic and the function element is secured in the hard plastic of the head. 